Hi Harry,
lgtm.
Btw, it looks like that the other patches from this series are already
applied to amd-staging-drm-next.
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
On 2021-10-27 10:26 a.m., Harry Wentland wrote:
There is no reason to allow for partial buffers from
userspace in our debugfs. In this particular case
callers will zero out the wr_buf but if callers in
the future don't do that we might be looking at
corrupt data.
Linus puts it better than I can in
https://lkml.org/lkml/2021/10/26/993
Signed-off-by: Harry Wentland <harry.wentland@xxxxxxx>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
index 1a68a674913c..b30307ccff12 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
@@ -78,12 +78,10 @@ static int parse_write_buffer_into_params(char *wr_buf, uint32_t wr_buf_size,
wr_buf_ptr = wr_buf;
- r = copy_from_user(wr_buf_ptr, buf, wr_buf_size);
-
- /* r is bytes not be copied */
- if (r >= wr_buf_size) {
- DRM_DEBUG_DRIVER("user data not be read\n");
- return -EINVAL;
+ /* r is bytes not be copied */
+ if (copy_from_user(wr_buf_ptr, buf, wr_buf_size)) {
+ DRM_DEBUG_DRIVER("user data could not be read successfully\n");
+ return -EFAULT;
}
/* check number of parameters. isspace could not differ space and \n */
